1. Technical Field
The present invention relates to a printing apparatus and a printing method.
2. Related Art
According to the related art, when predetermined printing is performed with respect to a print medium, reference marks indicating a cutting position called a dragonfly are printed in the vicinity of a target image, that is, four corners of the print medium. When printing is performed with respect to plural sheets of a print medium through a printing scheme using a plate such as offset printing, the same reference marks are printed onto all the sheets.
Further, there is known an existing printing method of printing a mark (black color) and a background color (red or white color), which is different from the mark color, in the vicinity of a predetermined surface of media to be cut or media to be printed, in order to increase contrast between the mark and the periphery of the mark (see JP-A-2006-212997).
However, plural sheets of a print medium are cut on the basis of reference marks printed on the uppermost sheet of the print medium in a state in which the plural sheets are collected and overlap each other.
As disclosed in JP-A-2006-212997, the reference marks may be printed together with a target image through an ink jet scheme using nozzles for ejecting ink droplets. However, if the ink droplets are not ejected in the vicinity of the opening of the nozzle for a predetermined period of time, moisture or solvent in the ink is evaporated through contact between the air and the ink in the nozzle, so that the viscosity of the ink may be increased. The increase of the viscosity of the ink may cause various ejection failures such as ejection of the ink droplets from the nozzle at abnormal timing or speed, a curve in the flight of the ink droplets, and non-ejection of the ink droplets. As described above, since the reference mark indicates the cutting position of the print medium, the cutting position is required to be indicated with high accuracy. However, if the reference mark is printed using the nozzle which may cause the ejection failures as described above, the reference mark may not be exactly printed at the position at which the reference mark must be printed.